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Using a USB key instead of a hard drive
NightGod:
--- Quote from: leapinlew on March 27, 2007, 07:58:37 pm ---
--- Quote from: ChadTower on March 27, 2007, 01:58:29 pm ---Fast access? Not sure about that. At least it would be easy to pop out and make changes.
My main concern would be how long it will hold up under the type of heavy usage this would need. These things aren't usually primary devices.
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I was under the impression that a USB key is much faster than a hard disk. I've booted machines from a USB key and loaded an OS on the key and it is quite fast.
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As long as you are using USB 2.0, it should be. In fact, Vista has an option to use a USB 2.0 device as RAM for the system-it's not as fast as on-board RAM, but it's definately faster than hard drive access.
blueznl:
Don't do writes. For example, create an image, load it at boot time fully into ram. Run it in ram. Just don't do writes.
This may not work with XP, but will work with Win98. Dunno if it would work with an embedded version of XP (it probably will, but I don't know if you need to run or can even run DirectX or something like that on embedded or PE).
USB's as well as many other flash ram based devices are good for repeated reads, just not for repeated writes. Even cheap sticks will work well. If you need an analogy think about a CD R/W...
dmckean:
Use Linux and run everything in RAM like others have said. I'm doing this in my cab and it works great, it took a little while to set up because I hadn't messed with Linux much before but once I got it up and running it worked great. RAM is cheap and MAME only needs about 256 meg anyway. If you go with a hard drive it's going to fail every 3 to 5 years on average if you run your cabinets 24 hours a day.
ChadTower:
I'm still not sure I believe that USB 2.0 is faster than an internal IDE directly on the system bus. I just don't see that happening. Too many factors against it, from latency due to distance, to number of conductors, to most basic design concepts. Sure, it would be faster than an external hard drive, but internal vanilla IDE? I'd have to see some very credible proof before believing that.
EDIT: FWIW, Wikipedia puts a PATA (aka IDE) drive's practical transfer speed, under average conditions, at 50-60MB/second. It also puts a full speed USB (all prior to 2.0 and many 2.0) device, not connected to a hub, at 12MB/second. A hi-speed USB (many 2.0 but certainly not all) has a theoretical max of 60MB/second but a usual performance max of 30MB/second, again only if not attached via a hub. USB devices attached via a hub all share the throughput max of the port to which the hub is attached, so if you have a 4 port hub each with a device, they would be sharing a usual 12MB/second throughput, and even then only ever achieving max individual performance if the USB hub in question has individual transaction translator for each hub port (not common in cheap hubs).
So, assuming he used a good hi-speed (make sure to check your specs, 2.0 is not hi-speed by spec) key, connected directly to its own motherboard port, he will get speeds of a third to half of internal IDE. Given that USB keys are known to slow down as their write cycles are used up, it won't be long before he's looking at a more expensive device with less capacity, much slower speeds, and a very finite lifespan if he uses a USB key as his primary storage device.
A 10g PATA/IDE drive is almost free and suffers none of those limitations.
hbm*rais:
No need to reinvent the wheel there, messing with ram disks and stuff yourself, or even learning the internals of linux. AdvanceCD can generate an ISO image that you can "burn" on a CD or pendrive.
Just download AdvanceCD. Put the roms in the right folder. Run the script that creates the image. Burn the image. You're done.
It's based on a Linux liveCD (like Knoppix), it will auto detect your hardware (hopefully) and boot into a frontend (AdvanceMenu. Granted not the greatest looking...).
It will run mostly from RAM, so it will limit the wear.
As for speed, it boots fast enough IIRC. If you're using a 1Gb pendrive, you probably don't intend to fill it with 60+Mb Neo Geo roms. For classics, load time should be a non-issue.